C# 上传下载ftp(支持断点续传)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net.Sockets;
using System.IO;
using System.Net;

namespace JianKunKing.Common.Ftp
{
/// <summary>
/// FTP Client(不允许匿名登录)
/// 上传、下载已测试，其余未测试
/// </summary>
public class FTPClient
{
#region 构造函数
/// <summary>
/// 缺省构造函数
/// </summary>
public FTPClient()
{
this.ftpServerIP = "";
this.remoteFilePath = "";
this.ftpUserID = "";
this.ftpPassword = "";
this.ftpServerPort = 21;
this.bConnected = false;
}

/// <summary>
/// 构造函数
/// </summary>
/// <param name="remoteHost">FTP服务器IP地址</param>
/// <param name="remotePath">当前服务器目录</param>
/// <param name="remoteUser">Ftp 服务器登录用户账号</param>
/// <param name="remotePass">Ftp 服务器登录用户密码</param>
/// <param name="remotePort">FTP服务器端口</param>
public FTPClient(string ftpServerIP, string remoteFilePath, string ftpUserID, string ftpPassword, int ftpServerPort, bool anonymousAccess = false)
{
this.ftpServerIP = ftpServerIP;
this.remoteFilePath = remoteFilePath;
this.ftpUserID = ftpUserID;
this.ftpPassword = ftpPassword;
this.ftpServerPort = ftpServerPort;
this.Connect();
}
#endregion

#region 登陆字段、属性
/// <summary>
/// FTP服务器IP地址
/// </summary>
private string ftpServerIP;
public string FtpServerIP
{
get
{
return ftpServerIP;
}
set
{
this.ftpServerIP = value;
}
}
/// <summary>
/// FTP服务器端口
/// </summary>
private int ftpServerPort;
public int FtpServerPort
{
get
{
return ftpServerPort;
}
set
{
this.ftpServerPort = value;
}
}
/// <summary>
/// 当前服务器目录
/// </summary>
private string remoteFilePath;
public string RemoteFilePath
{
get
{
return remoteFilePath;
}
set
{
this.remoteFilePath = value;
}
}
/// <summary>
/// Ftp 服务器登录用户账号
/// </summary>
private string ftpUserID;
public string FtpUserID
{
set
{
this.ftpUserID = value;
}
}
/// <summary>
/// Ftp 服务器用户登录密码
/// </summary>
private string ftpPassword;
public string FtpPassword
{
set
{
this.ftpPassword = value;
}
}

/// <summary>
/// 是否登录
/// </summary>
private bool bConnected;
public bool Connected
{
get
{
return this.bConnected;
}
}
#endregion

#region 链接
/// <summary>
/// 建立连接
/// </summary>
public void Connect()
{
socketControl = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint ep = new IPEndPoint(IPAddress.Parse(FtpServerIP), ftpServerPort);
// 链接
try
{
socketControl.Connect(ep);
}
catch (Exception)
{
throw new IOException("Couldn't connect to remote server");
}

// 获取应答码
ReadReply();
if (iReplyCode != 220)
{
DisConnect();
throw new IOException(strReply.Substring(4));
}

// 登陆
SendCommand("USER " + ftpUserID);
if (!(iReplyCode == 331 || iReplyCode == 230))
{
CloseSocketConnect();//关闭连接
throw new IOException(strReply.Substring(4));
}
if (iReplyCode != 230)
{
SendCommand("PASS " + ftpPassword);
if (!(iReplyCode == 230 || iReplyCode == 202))
{
CloseSocketConnect();//关闭连接
throw new IOException(strReply.Substring(4));
}
}

bConnected = true;

// 切换到初始目录
if (!string.IsNullOrEmpty(remoteFilePath))
{
ChDir(remoteFilePath);
}
}

/// <summary>
/// 关闭连接
/// </summary>
public void DisConnect()
{
if (socketControl != null)
{
SendCommand("QUIT");
}
CloseSocketConnect();
}

#endregion

#region 传输模式

/// <summary>
/// 传输模式:二进制类型、ASCII类型
/// </summary>
public enum TransferType
{
Binary,
ASCII
};

/// <summary>
/// 设置传输模式
/// </summary>
/// <param name="ttType">传输模式</param>
public void SetTransferType(TransferType ttType)
{
if (ttType == TransferType.Binary)
{
SendCommand("TYPE I");//binary类型传输
}
else
{
SendCommand("TYPE A");//ASCII类型传输
}
if (iReplyCode != 200)
{
throw new IOException(strReply.Substring(4));
}
else
{
trType = ttType;
}
}

/// <summary>
/// 获得传输模式
/// </summary>
/// <returns>传输模式</returns>
public TransferType GetTransferType()
{
return trType;
}

#endregion

#region 文件操作
/// <summary>
/// 获得文件列表
/// </summary>
/// <param name="strMask">文件名的匹配字符串</param>
/// <returns></returns>
public string[] Dir(string strMask)
{
// 建立链接
if (!bConnected)
{
Connect();
}

//建立进行数据连接的socket
Socket socketData = CreateDataSocket();

//传送命令
SendCommand("LIST " + strMask);

//分析应答代码
if (!(iReplyCode == 150 || iReplyCode == 125 || iReplyCode == 226))
{
throw new IOException(strReply.Substring(4));
}

//获得结果
strMsg = "";
while (true)
{
int iBytes = socketData.Receive(buffer, buffer.Length, 0);
strMsg += GB2312.GetString(buffer, 0, iBytes);
if (iBytes < buffer.Length)
{
break;
}
}
char[] seperator = { '\n' };
string[] strsFileList = strMsg.Split(seperator);
socketData.Close();//数据socket关闭时也会有返回码
if (iReplyCode != 226)
{
ReadReply();
if (iReplyCode != 226)
{
throw new IOException(strReply.Substring(4));
}
}
return strsFileList;
}

/// <summary>
/// 获取文件大小
/// </summary>
/// <param name="strFileName">文件名</param>
/// <returns>文件大小</returns>
public long GetFileSize(string strFileName)
{
if (!bConnected)
{
Connect();
}
SendCommand("SIZE " + Path.GetFileName(strFileName));
long lSize = 0;
if (iReplyCode == 213)
{
lSize = Int64.Parse(strReply.Substring(4));
}
else
{
throw new IOException(strReply.Substring(4));
}
return lSize;
}

/// <summary>
/// 删除
/// </summary>
/// <param name="strFileName">待删除文件名</param>
public void Delete(string strFileName)
{
if (!bConnected)
{
Connect();
}
SendCommand("DELE " + strFileName);
if (iReplyCode != 250)
{
throw new IOException(strReply.Substring(4));
}
}

/// <summary>
/// 重命名(如果新文件名与已有文件重名,将覆盖已有文件)
/// </summary>
/// <param name="strOldFileName">旧文件名</param>
/// <param name="strNewFileName">新文件名</param>
public void Rename(string strOldFileName, string strNewFileName)
{
if (!bConnected)
{
Connect();
}
SendCommand("RNFR " + strOldFileName);
if (iReplyCode != 350)
{
throw new IOException(strReply.Substring(4));
}
//  如果新文件名与原有文件重名,将覆盖原有文件
SendCommand("RNTO " + strNewFileName);
if (iReplyCode != 250)
{
throw new IOException(strReply.Substring(4));
}
}
#endregion

#region 上传和下载
/// <summary>
/// 下载一批文件
/// </summary>
/// <param name="strFileNameMask">文件名的匹配字符串</param>
/// <param name="strFolder">本地目录(不得以\结束)</param>
public void Download(string strFileNameMask, string strFolder)
{
if (!bConnected)
{
Connect();
}
string[] strFiles = Dir(strFileNameMask);
foreach (string strFile in strFiles)
{
if (!strFile.Equals(""))//一般来说strFiles的最后一个元素可能是空字符串
{
if (strFile.LastIndexOf(".") > -1)
{
Download(strFile.Replace("\r", ""), strFolder, strFile.Replace("\r", ""));
}
}
}
}

/// <summary>
/// 下载目录
/// </summary>
/// <param name="strRemoteFileName">要下载的文件名</param>
/// <param name="strFolder">本地目录(不得以\结束)</param>
/// <param name="strLocalFileName">保存在本地时的文件名</param>
public void Download(string strRemoteFileName, string strFolder, string strLocalFileName)
{
if (strLocalFileName.StartsWith("-r"))
{
string[] infos = strLocalFileName.Split(' ');
strRemoteFileName = strLocalFileName = infos[infos.Length - 1];
if (!this.bConnected)
{
this.Connect();
}
SetTransferType(TransferType.Binary);
if (strLocalFileName.Equals(""))
{
strLocalFileName = strRemoteFileName;
}
if (!File.Exists(strLocalFileName))
{
Stream st = File.Create(strLocalFileName);
st.Close();
}
FileStream output = new
FileStream(strFolder + "\\" + strLocalFileName, FileMode.Create);
Socket socketData = CreateDataSocket();
SendCommand("RETR " + strRemoteFileName);
if (!(iReplyCode == 150 || iReplyCode == 125
|| iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
int receiveBytes = 0;
while (true)
{
int iBytes = socketData.Receive(buffer, buffer.Length, 0);
receiveBytes = receiveBytes + iBytes;
output.Write(buffer, 0, iBytes);
if (iBytes <= 0)
{
break;
}
}
output.Close();
if (socketData.Connected)
{
socketData.Close();
}
if (!(iReplyCode == 226 || iReplyCode == 250))
{
ReadReply();
if (!(iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
}
}
}

/// <summary>
/// 下载一个文件
/// </summary>
/// <param name="strRemoteFileName">要下载的文件名</param>
/// <param name="strFolder">本地目录(不得以\结束)</param>
/// <param name="strLocalFileName">保存在本地时的文件名</param>
public void DownloadFile(string strRemoteFileName, string strFolder, string strLocalFileName)
{
if (!bConnected)
{
Connect();
}
SetTransferType(TransferType.Binary);
if (strLocalFileName.Equals(""))
{
strLocalFileName = strRemoteFileName;
}
if (!File.Exists(strLocalFileName))
{
Stream st = File.Create(strLocalFileName);
st.Close();
}

FileStream output = new
FileStream(strFolder + "\\" + strLocalFileName, FileMode.Create);
Socket socketData = CreateDataSocket();
SendCommand("RETR " + strRemoteFileName);
if (!(iReplyCode == 150 || iReplyCode == 125
|| iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
while (true)
{
int iBytes = socketData.Receive(buffer, buffer.Length, 0);
output.Write(buffer, 0, iBytes);
if (iBytes <= 0)
{
break;
}
}
output.Close();
if (socketData.Connected)
{
socketData.Close();
}
if (!(iReplyCode == 226 || iReplyCode == 250))
{
ReadReply();
if (!(iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
}
}

/// <summary>
/// 下载一个文件(断点续传)
/// </summary>
/// <param name="strRemoteFileName">要下载的文件名</param>
/// <param name="strFolder">本地目录(不得以\结束)</param>
/// <param name="strLocalFileName">保存在本地时的文件名</param>
/// <param name="size">已下载文件流长度</param>
public void DownloadBrokenFile(string strRemoteFileName, string strFolder, string strLocalFileName, long size)
{
if (!bConnected)
{
Connect();
}
SetTransferType(TransferType.Binary);
FileStream output = new
FileStream(strFolder + "\\" + strLocalFileName, FileMode.Append);
Socket socketData = CreateDataSocket();
SendCommand("REST " + size.ToString());
SendCommand("RETR " + strRemoteFileName);
if (!(iReplyCode == 150 || iReplyCode == 125
|| iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
while (true)
{
int iBytes = socketData.Receive(buffer, buffer.Length, 0);
output.Write(buffer, 0, iBytes);
if (iBytes <= 0)
{
break;
}
}
output.Close();
if (socketData.Connected)
{
socketData.Close();
}
if (!(iReplyCode == 226 || iReplyCode == 250))
{
ReadReply();
if (!(iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
}
}

/// <summary>
/// 上传一批文件
/// </summary>
/// <param name="strFolder">本地目录(不得以\结束)</param>
/// <param name="strFileNameMask">文件名匹配字符(可以包含*和?)</param>
public void Upload(string strFolder, string strFileNameMask)
{
string[] strFiles = Directory.GetFiles(strFolder, strFileNameMask);
foreach (string strFile in strFiles)
{
//strFile是完整的文件名(包含路径)
Upload(strFile);
}
}

/// <summary>
/// 上传一个文件
/// </summary>
/// <param name="strFileName">本地文件名</param>
public void Upload(string strFileName)
{
if (!bConnected)
{
Connect();
}
Socket socketData = CreateDataSocket();
SendCommand("STOR " + Path.GetFileName(strFileName));
if (!(iReplyCode == 125 || iReplyCode == 150))
{
throw new IOException(strReply.Substring(4));
}
FileStream input = new
FileStream(strFileName, FileMode.Open);
int iBytes = 0;
while ((iBytes = input.Read(buffer, 0, buffer.Length)) > 0)
{
socketData.Send(buffer, iBytes, 0);
}
input.Close();
if (socketData.Connected)
{
socketData.Close();
}
if (!(iReplyCode == 226 || iReplyCode == 250))
{
ReadReply();
if (!(iReplyCode == 226 || iReplyCode == 250))
{
throw new IOException(strReply.Substring(4));
}
}
}

#endregion

#region 目录操作
/// <summary>
/// 创建目录
/// </summary>
/// <param name="strDirName">目录名</param>
public void MkDir(string strDirName)
{
if (!bConnected)
{
Connect();
}
SendCommand("MKD " + strDirName);
if (iReplyCode != 257)
{
throw new IOException(strReply.Substring(4));
}
}

/// <summary>
/// 删除目录
/// </summary>
/// <param name="strDirName">目录名</param>
public void RmDir(string strDirName)
{
if (!bConnected)
{
Connect();
}
SendCommand("RMD " + strDirName);
if (iReplyCode != 250)
{
throw new IOException(strReply.Substring(4));
}
}

/// <summary>
/// 改变目录
/// </summary>
/// <param name="strDirName">新的工作目录名</param>
public void ChDir(string strDirName)
{
if (strDirName.Equals(".") || strDirName.Equals(""))
{
return;
}
if (!bConnected)
{
Connect();
}
SendCommand("CWD " + strDirName);
if (iReplyCode != 250)
{
throw new IOException(strReply.Substring(4));
}
this.remoteFilePath = strDirName;
}

#endregion

#region 内部变量
/// <summary>
/// 服务器返回的应答信息(包含应答码)
/// </summary>
private string strMsg;
/// <summary>
/// 服务器返回的应答信息(包含应答码)
/// </summary>
private string strReply;
/// <summary>
/// 服务器返回的应答码
/// </summary>
private int iReplyCode;
/// <summary>
/// 进行控制连接的socket
/// </summary>
private Socket socketControl;
/// <summary>
/// 传输模式
/// </summary>
private TransferType trType;
/// <summary>
/// 接收和发送数据的缓冲区
/// </summary>
private static int BLOCK_SIZE = 512;
Byte[] buffer = new Byte[BLOCK_SIZE];
/// <summary>
/// 编码方式(为防止出现中文乱码采用 GB2312编码方式)
/// </summary>
Encoding GB2312 = Encoding.GetEncoding("gb2312");
#endregion

#region 内部函数
/// <summary>
/// 将一行应答字符串记录在strReply和strMsg
/// 应答码记录在iReplyCode
/// </summary>
private void ReadReply()
{
strMsg = "";
strReply = ReadLine();
iReplyCode = Int32.Parse(strReply.Substring(0, 3));
}

/// <summary>
/// 建立进行数据连接的socket
/// </summary>
/// <returns>数据连接socket</returns>
private Socket CreateDataSocket()
{
SendCommand("PASV");
if (iReplyCode != 227)
{
throw new IOException(strReply.Substring(4));
}
int index1 = strReply.IndexOf('(');
int index2 = strReply.IndexOf(')');
string ipData =
strReply.Substring(index1 + 1, index2 - index1 - 1);
int[] parts = new int[6];
int len = ipData.Length;
int partCount = 0;
string buf = "";
for (int i = 0; i < len && partCount <= 6; i++)
{
char ch = Char.Parse(ipData.Substring(i, 1));
if (Char.IsDigit(ch))
buf += ch;
else if (ch != ',')
{
throw new IOException("Malformed PASV strReply: " +
strReply);
}
if (ch == ',' || i + 1 == len)
{
try
{
parts[partCount++] = Int32.Parse(buf);
buf = "";
}
catch (Exception)
{
throw new IOException("Malformed PASV strReply: " +
strReply);
}
}
}
string ipAddress = parts[0] + "." + parts[1] + "." +
parts[2] + "." + parts[3];
int port = (parts[4] << 8) + parts[5];
Socket s = new
Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
IPEndPoint ep = new
IPEndPoint(IPAddress.Parse(ipAddress), port);
try
{
s.Connect(ep);
}
catch (Exception)
{
throw new IOException("Can't connect to remote server");
}
return s;
}

/// <summary>
/// 关闭socket连接(用于登录以前)
/// </summary>
private void CloseSocketConnect()
{
if (socketControl != null)
{
socketControl.Close();
socketControl = null;
}
bConnected = false;
}

/// <summary>
/// 读取Socket返回的所有字符串
/// </summary>
/// <returns>包含应答码的字符串行</returns>
private string ReadLine()
{
while (true)
{
int iBytes = socketControl.Receive(buffer, buffer.Length, 0);
strMsg += GB2312.GetString(buffer, 0, iBytes);
if (iBytes < buffer.Length)
{
break;
}
}
char[] seperator = { '\n' };
string[] mess = strMsg.Split(seperator);
if (strMsg.Length > 2)
{
strMsg = mess[mess.Length - 2];
//seperator[0]是10,换行符是由13和0组成的,分隔后10后面虽没有字符串,
//但也会分配为空字符串给后面(也是最后一个)字符串数组,
//所以最后一个mess是没用的空字符串
//但为什么不直接取mess[0],因为只有最后一行字符串应答码与信息之间有空格
}
else
{
strMsg = mess[0];
}
if (!strMsg.Substring(3, 1).Equals(" "))//返回字符串正确的是以应答码(如220开头,后面接一空格,再接问候字符串)
{
return ReadLine();
}
return strMsg;
}

/// <summary>
/// 发送命令并获取应答码和最后一行应答字符串
/// </summary>
/// <param name="strCommand">命令</param>
private void SendCommand(String strCommand)
{
Byte[] cmdBytes =
GB2312.GetBytes((strCommand + "\r\n").ToCharArray());
socketControl.Send(cmdBytes, cmdBytes.Length, 0);
ReadReply();
}

#endregion

}

}